Basal plane dislocation reduction in nitrogen doped 8° 4H-SiC epilayers

In summary, this work has shown that the mechanism by which BPDs are converted to TEDs is dependent on carrier concentration and type in 8° off-cut SiC epilayers. The conversion process takes place throughout the epilayer for UID-p films, even when an interrupt is employed, while low nitrogen doped films exhibit an abrupt increase in conversion at interrupts. High levels of nitrogen doping in the film prior to the interrupt drastically reduce the conversion efficiency. Therefore, it is imperative to better understand the role of nitrogen on the BPD conversion process to achieve full annihilation of BPDs in an n+ buffer layer for reliable bipolar devices.